Communication device, communication program, and recording medium recording communication program

ABSTRACT

A communication device accurately reports the position a vehicle or a pedestrian with respect to a local vehicle and supports safer driving. The communication device is mounted on a moving body and includes a communication unit that receives communication information according to a preset communication condition, a determination unit that determines whether a service is provided in accordance with the received communication information and a display controller that displays display information needed to provide the service on a map displayed on a display unit, when the service is provided according to a result determined by the determination unit.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of U.S. application Ser. No.15/694,178 filed Sep. 1, 2017, which is based upon and claims thebenefit of priority of the prior Japanese Patent Application No.2016-176626, filed on Sep. 9, 2016. The entire contents of each of theabove-identified applications are incorporated herein by reference.

FIELD

The present embodiment relate to a communication device mounted on amoving body, a communication program, and a recording medium thatrecords the communication program.

BACKGROUND

Currently, vehicle-to-everything communication (V2X communication) isproposed in which vehicles and an infrastructure cooperate with eachother, and the vehicles and various objects (such as vehicles, trafficsignals, persons, bicycles, or motorcycles) communicate with each othersuch that information can be exchanged. By using V2X communication,various attempts have been made to achieve a safe and efficient trafficsystem.

As an example, in order to support: safe driving, a technology has beenconsidered for determining whether a vehicle or a pedestrian existsaround a driver, by utilizing information obtained in V2X communication,and for displaying information (an attention-attracting display)indicating the existence of the vehicle or the pedestrian when thevehicle or the pedestrian exists.

SUMMARY

According to an aspect or the present embodiment 5, communication devicemounted on a moving body includes: a communication unit that receivescommunication information according to a preset communication condition;a determination unit that determines whether a prescribed service willbe provided in accordance with the received communication information;and a display controller that displays display information needed toprovide the prescribed service on a map displayed on a display unit,when the prescribed service is to be provided according to adetermination result.

According to an aspect of the present embodiments, a communicationdevice mounted on a moving body includes a processor to receivecommunication information according to a preset communication condition,to determine whether a service is provided in accordance with thereceived communication information, and to display display informationneeded to provide the service on a map displayed on a display unit, whenthe service is provided.

Further, according to an aspect of the present embodiments, anon-transitory computer readable recording medium is provided that, hasrecorded therein a communication program for causing a communicationdevice mounted on a moving body to receive communication informationaccording to a preset communication condition, to determine whether aprescribed service will be provided in accordance with the receivedcommunication information, and to display display information needed toprovide the prescribed service on a map displayed on a display unit,when the prescribed service is to be provided according to adetermination result.

The object and advantages of the embodiment will be realized andattained by means of the elements and combinations particularly pointedout in the claims.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and explanatory and arenot restrictive of the embodiment.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram illustrating a communication systemincluding a communication device according to an embodiment at anintersection.

FIG. 2 is a block diagram illustrating the communication systemincluding the communication device according to the embodiment.

FIG. 3 illustrates an example of a transmission format according to theembodiment.

FIG. 4 is a diagram explaining a right-turn collision prevention supportservice.

FIG. 5 is a diagram explaining a left-turn collision prevention supportservice.

FIG. 6 is a diagram explaining a collision-upon-encounter preventionsupport service.

FIG. 7 is a block diagram illustrating an example of a functionconfiguration of the communication device according to the embodiment.

FIG. 8 illustrates an example of a hardware configuration forimplementing the communication device according to the embodiment.

FIG. 9 is a sequence chart illustrating an example of a sequenceillustrating processing for providing a prescribed service of thecommunication device according to the embodiment.

FIG. 10 is a flowchart illustrating an example of a flow of processingfor providing a prescribed service of the communication device accordingto the embodiment.

FIG. 11A illustrates an example of a display in which a positionalrelationship on a map between a specified vehicle and the local vehicleis viewed from the top according to the embodiment.

FIG. 11B illustrates an example of a display in winch a specifiedvehicle approaching the local vehicle is viewed from a side of the localvehicle according to the embodiment.

FIG. 12 is a diagram explaining a display on a map of a travelling routeof a specified vehicle in a case in which the specified vehicle existsaround the local vehicle according to the embodiment.

FIG. 13 illustrates an example of a display in a right turn collisionprevention support service.

DESCRIPTION OF THE EMBODIMENTS

Embodiments of the present invention a e described below in detail withreference to the drawings

FIG. 1 is a schematic diagram illustrating a communication system 1including a communication device 3 (3 a to 3 d) according to anembodiment at an intersection. FIG. 2 is a block diagram illustrating aportion of the communication system 1 including the communication device3 according to the embodiment. As illustrated in FIG. 1, thecommunication system 1 is configured by a communication device 3 (3 a to3 d) that can be mounted on a vehicle 2 (2 a to 2 d) and a roadsidemachine 4 (4 a and 4 b). Here, the communication system 1 is describedby using an intersection as an example, but the communication system 1is not always utilized at the intersection, and the communication system1 can also be utilized in other place (for example, a junction in which,roadways join together).

FIG. 1 illustrates four vehicles 2 (2 a to 2 d) that enter anintersection including traffic signals 5 (5 a 5 b), and thecommunication device 3 (3 a to 3 d) is mounted on each of the vehicles2. FIG. 1 also illustrates a pedestrian 7 who is about to cross acrosswalk 6 at the intersection. In this example, the vehicle 2 is amoving body such as a four-wheeled vehicle, a two-wheeled vehicle, or abicycle. In addition, the communication device 3 is not limited, forexample, to a car navigate device installed onto a vehicle, and may be,for example, a portable terminal such as a smartphone having navigationfunction.

The configuration of the communication system 1 is not limited to theconfiguration above, and the communication system 1 may haveconfiguration in which one roadside machine 4 is installed at oneintersection without installing one roadside machine 4 onto each of thetraffic signals 5.

In FIG. 1, only the vehicles 2 enter the intersection, but in a case inwhich a pedestrian who possesses a portable communication device 3 suchenters as a the smartphone intersection, the communication device 3 thatis possessed by the pedestrian may become a component of thecommunication system 1, similarly to the communication device 3 mountedon the vehicle 2. In this case, the pedestrian, who is a moving body,corresponds to the vehicle 2. The communication device 3 possessed bythe pedestrian can perform V2X communication with another communicationdevice 3 and the like, and can communicate information with thecommunication device 3 mounted on the vehicle 2 or the roadside machine4 such that the prescribed service described later can be provided tothe pedestrian. In other words, the communication device 3 possessed bythe pedestrian corresponds to a communication device mounted on a movingbody.

The roadside machine 4 is installed in a place in which V2Xcommunication can be performed with the communication device 3 (forexample, at a roadside, in an intersection, or the like), and theroadside machine 4 detects, for example, a vehicle or a pedestrian inthe intersection, or a vehicle or a pedestrian that approaches theintersection, by using a sensor. The roadside machine 4 regularly orirregularly outputs a detection result (roadside machine information) tothe outside in V2X communication. As an example, the roadside machine 4regularly or irregularly output the detection result (the roadsideinformation) to the outside at a frequency of at least several tens oftimes per second in V2X communication. The output roadside machineinformation is received, for example, by the communication device 3mounted on the vehicle 2 entering the intersection or the communicationdevice 3 possessed by the pedestrian entering the intersection.

The roadside machine 4 may be a portion of the configuration of atraffic signal, or may be configured to be independent of the trafficsignal. Road-vehicle V2X communication that is performed between aninfrastructure such as the roadside machine 4 and the communicationdevice 3, as described above, is referred to as road-vehiclecommunication, Inter-vehicle V2X communication that is performed betweenthe communication devices 3, as described later, is referred to asinter-vehicle communication, and is communication that is performed, forexample, between the communication device 3 a and the communicationdevice 3 b.

Information obtained in road-vehicle V2X communication or inter-vehicleV2X communication is referred to as V2X information (communicationinformation). Examples of the content of road-vehicle V2X informationinclude information relating to a waiting time at a red light,information relating to the shape of a road, information relating to thenumber of road lanes, and information relating to a travelling directionof a vehicle. Examples of the content of inter-vehicle V2X informationinclude identification information (ID) of the communication device 3 orthe vehicle 2 mounted with the communication device 3, informationrelating to the position of the vehicle 2, information relating to thespeed of the vehicle 2, and information relating to the size of thevehicle 2. The V2X information is not limited to the information above,and may include any other information needed to support safe driving.

The V2X information is not limited to information obtained in roadvehicle V2X communication or inter vehicle V2X communication. Namely,the V2X information may include emergency information reported from anemergency information reporting system in V2X communication, such asdisaster information, emergency vehicle information, or ambulanceinformation that is obtained by utilizing a satellite system such as aglobal navigation satellite system (GNSS).

A preset communication condition is, for example, a condition whereinV2X information relating to V2X is directly communicated between a roadand a vehicle or between vehicles. The preset communication condition isnot limited to the condition wherein the V2X information relating to V2Xis directly communicated between a road and a vehicle or betweenvehicles. The preset communication condition may be a condition whereincommunication is indirectly performed via a network such as theInternet. When communication is indirectly performed via the networksuch as the Internet, the communication system 1 can use, for example, acommunication line between cellular phones.

Here, details of the communication device 3 are described. Thecommunication device 3 first receives the V2X information (thecommunication information) according to the preset communicationcondition.

Specifically, the communication device 3 (3 a) obtains V2X information(roadside machine information) from the roadside machine 4 a via acommunication driver 20 in V2X communication, and stores the V2Xinformation in a road-vehicle primary DB 21 a, as illustrated in FIG. 2.The stored roadside machine information is subjected to processingneeded to update each service by using a roadside machine system servicemanagement function 25, and is stored in a road-vehicle secondary DB 21b. Namely, the communication device 3 a stores the roadside machineinformation obtained from the roadside machine 4 a in the road-vehicleprimary DB 21 a, processes the roadside machine information, and storesthe processed information in the road-vehicle secondary DB 21 b.

In addition, the communication device 3 (3 a) obtains V2X information(another-vehicle information) from another communication device 3 b viathe communication driver 20 in V2X communication, and stores theanother-vehicle information in an inter-vehicle primary DB 22 a, asillustrated in FIG. 2. The stored another-vehicle information issubjected to processing needed to update each of the services by usingan inter-vehicle system service management function 26, and theprocessed information is stored in an inter-vehicle secondary DB 22 b.Namely, the communication device 3 a stores another-vehicle informationrelating to the vehicle 2 b that is obtained from the communicationdevice 3 b in the inter-vehicle primary DB 22 a, processes theanother-vehicle information, and stores the processed another vehicleinformation in the inter-vehicle secondary DB 22 b.

Further, the communication device 3 (3 a) includes a local-vehicleposition update function 29 that updates the position of the vehicle 2(2 a), and updates a local-vehicle position when the position of thevehicle 2 changes, for example, due to travelling, as illustrated inFIG. 2. Information relating to the updated local-vehicle position(local-vehicle position information) is stored in a local-vehicleinformation DB 23. In the local-vehicle information DB 23, variableinformation, such as information relating to the speed of the localvehicle that is detected by a not-illustrated detector, informationrelating to opening or closing of an accelerator, information relatingto a brake, information relating o a steering angle of a steering wheel,information indicated by a direction indicator, or information relatingto a turn-on state of a head light, variable information such asprescribed size, type, or the like of a vehicle, and other informationare also stored. The local-vehicle position information and theinformation above such as the speed information are managed aslocal-vehicle information (vehicle information), and the local-vehicleinformation is output to the outside via the communication driver 20. Inaddition, the local-vehicle information is transferred to the roadsidemachine system service management function 25 and the inter-vehiclesystem service management function 26.

Here, an example of a transmission format when outputting the V2Xinformation to the outside is described. The transmission formatincludes a header portion and a data portion, as illustrated in FIG. 3,for example. Information such as a transmission source (the roadsidemachine 4, the communication device 3, or the like) is stored in theheader portion, and the V2X information or the like is stored in thedata portion. The data portion may include an area (a free area) towhich information is freely written. The presence of the area to whichinformation is freely written enables a higher-quality service (supportinformation) to be provided according to a user (a driver or the like).

Return now to the description of the communication device 3. Thecommunication device 3 provides a prescribed service (supportinformation) for supporting safe driving in accordance with the obtainedV2X information (the roadside machine information or the vehicleinformation) and the local-vehicle information. Namely, thecommunication device 3 determines whether a prescribed service should beprovided to a driver in accordance with the obtained V2X information andthe local-vehicle information. According to a determination result, whenthe prescribed service should be provided, the communication device 3displays display information needed to provide the prescribed service ona map displayed on a display unit such as a navigation display 30 suchthat the display information superimposed onto the map. The displayinformation is an icon or character information that can be visuallyrecognized on the map, and as an example, in the case of the right-turncollision prevention support service described later, the displayinformation refers to an icon or character information that indicates anoncoming vehicle or the pedestrian 7 crossing the crosswalk 6.

Specifically, the communication device 3 (3 a) updates respectiveprescribed services in accordance with the roadside machine informationstored in the road-vehicle secondary DB 21 b and the local-vehicleinformation by using the roadside machine system service managementfunction 25, as illustrated in FIG. 2. An update result is stored in aroad-vehicle tertiary DB 21 c. In addition, the communication device 3(3 a) updates respective prescribed services in accordance with theanother-vehicle information stored in the inter-vehicle secondary DB 22b and the local vehicle information by using the inter-vehicle systemservice management function 26. An update result is stored in aninter-vehicle tertiary DB 22 c.

Updating of a prescribed service refers to updating of information usedto determine whether the prescribed service should be provided, andrefers, for example, to updating of position information of anothervehicle, a pedestrian, or the like with respect to the local vehicle.

In this example, the primary to tertiary road-vehicle DBs and theprimary to tertiary inter-vehicle DBs are provided, but these DBs may beintegrated into one DB. In addition, the roadside machine system servicemanagement function 25 and the inter-vehicle system service managementfunction 26 individually update services, but these functions may beintegrated, and the integrated function may collectively updateservices.

The communication device 3 (3 a) determines whether a prescribed serviceshould be provided in accordance with the update results stored in theroad-vehicle tertiary DB 21 ca and the inter-vehicle tertiary DB 22 c.When it is determined that the prescribed service should be provided,the communication device 3 (3 a) obtains information needed to providethe prescribed service. The obtained information is stored as displayinformation in a V2X display information DB 24. The communication device3 (3 a) causes a map display function 28 to display characters, an icon,or the like on a map of the navigation display in accordance with thedisplay information stored in the V2X display information DB 24.

An example of a prescribed service provided to support safe driving isdescribed next.

First, a right-turn/left turn collision prevention support service isdescribed with reference to FIG. 4 and FIG. 5. FIG. 4 is a diagramexplaining a right-turn collision prevention support service, and FIG. 5is a diagram explaining a left-turn collision prevention supportservice.

At the time of turning to the right, as illustrated in FIG. 4, acommunication device mounted on the vehicle 2 obtains roadside machineinformation (in this example, information relating to a pedestrian 40)from the roadside machine 4, and also obtains vehicle information of anoncoming vehicle 41 from another communication device mounted on theoncoming vehicle 41. In addition, the communication device mounted onthe vehicle 2 obtains vehicle information indicating a right-hand turnas the local-vehicle information on the basis of, for example, the speedinformation of the local vehicle that has been detected by a detectorand information relating to blinking of a right-hand blinker, which isthe information indicated by the direction indicator. At the time ofturning to the left, as illustrated in FIG. 5, the communication devicemounted on the vehicle 2 obtains roadside machine information (in thisexample, the information relating to the pedestrian 40) from theroadside machine 4. The communication device mounted on the vehicle 2obtains vehicle information indicating left-hand turn as thelocal-vehicle information on the basis of, for example, the speedinformation of the local vehicle that has been detected by a detectorand information relating to blinking of a left-hand blinker, which isthe information indicated by the direction indicator. At the time ofturning to the left, an oncoming vehicle does not need to be considered,as it docs at the time of a turn to the right. However, when amotorcycle, a bicycle, or the like is travelling in parallel or, aleft-hand side of the travelling vehicle 2, inter-vehicle communicationmay be performed with the motorcycle, the bicycle, or the like such thatvehicle information is obtained. By doing this, a collision accidentgenerated at the time of turning to the left can be prevented.

The communication device mounted the vehicle 2 determines whether apedestrian or the like that is obstructing travel exists in accordancewith the roadside machine information and the vehicle information thathave been obtained, and reports information to a driver when an obstacleexists.

Reporting information to a driver refers, for example, to displaying anicon or the like that indicates a vehicle or a pedestrian at acorresponding point on a map 130 on a navigation screen or acorresponding point on an enlarged map 131 obtained by enlarging acorresponding intersection on the map 130, as illustrated in FIG. 13. Atthis time, an arrow indicating a travelling direction (for example, anarrow indicating right-hand turn) and a mark for attracting attentionmay be displayed, for example, in a middle portion of a tachometer 132,When displaying them, a map may be further enlarged. In this example,the enlarged map 131 is displayed on a screen between the tachometer 132and a speed meter 133, and an icon 134 that indicates a pedestriancrossing a crosswalk at an intersection and an icon 135 that indicatesan oncoming vehicle approaching the local vehicle are displayed on theenlarged map 131. By doing this, which position a vehicle or apedestrian exists in with respect to the local vehicle can be accuratelygrasped, and safer driving can be performed. The map 130 is displayed ona screen below the enlarged map 131. Map information that causes the map130 on the navigation screen to be displayed includes informationrelating to nodes that are nodal points in a road network expressionincluding an intersection and the like, and information relating tolinks that are road sections between the nodes.

The display above may be linked with depression of an accelerator pedalor a brake pedal or with a direction indicator. In addition, informationrelating to the switching of the color of a traffic signal (for example,a remaining time before the traffic signal switched from green to red)may be displayed together with information relating to the pedestrian orthe vehicle. The display manner above is not applied only to theright-turn/left-turn collision prevention support service, and can alsobe applied to another support service for safe driving,

A collision-upon-encounter prevention support service is described nextwith reference to FIG. 6. The communication device mounted on thevehicle 2 obtains vehicle information of vehicles 60 and 61 entering anintersection without a traffic signal from leftward and rightwarddirections from respective communication devices mounted on the vehicles60 and 61 in inter-vehicle communication. The communication devicemounted on the vehicle 2 obtains vehicle information indicating aleft-hand turn as local-vehicle information speed on the basis of speedinformation of the local vehicle and information indicated by adirection indicator. The communication device mounted on the vehicle 2determines whether the vehicles entering the intersection obstructtravelling of the local vehicle on the basis of the obtained vehicleinformation, and when the vehicles obstruct travelling, thecommunication device mounted on the vehicle 2 displays icons orcharacter information indicating the vehicles 60 and 61 in correspondingpositions on a map on a navigation screen. The communication devicemounted on the vehicle 2 obtains the speed information of the vehicle 60on the basis of, for example, position information of the vehicle 60 anda change in the position information. The communication device mountedon the vehicle 2 determines whether the vehicle 60 and the vehicle 2 arelocated within a specified range after a prescribed time period on thebasis of, for example, the position information of the vehicle 60, thespeed information of the vehicle 60, the position information of thevehicle 2, the speed information of the vehicle 2, and the vehicleinformation indicating a left-hand turn that have been obtained. Thecommunication device mounted on the vehicle 2 determines that thevehicle 60, which is entering the intersection, obstructs travelling ofthe local vehicle, for example, when the vehicle 60 and the vehicle 2are located within the specified range after the prescribed time period.The communication device mounted on the vehicle 2 determines that thevehicle 60, which is entering the intersection, does not obstructtravelling of the local vehicle, for example, when the vehicle 60 andthe vehicle 2 are not located within the specified range after theprescribed time period. By doing this, the existence of a vehicle or apedestrian that a driver fails to see due to a blind spot can begrasped, and safe driving can be supported.

A support service for reporting the approach of a special vehicle (suchas a construction vehicle, an emergency vehicle, or a public vehicle) toa driver in accordance with V2X information is provided, for example, inaddition to the support services described above. In the case of thesupport service for reporting the approach of the special vehicle to adriver according to V2X information, the communication device mounted onthe vehicle 2 can obtain, for example, a difference in the type of thespecial vehicle, such as a construction vehicle, an emergency vehicle,or a public vehicle, in inter-vehicle communication.

As another support service, a large number of icons or the like thatindicate persons can be displayed on a map that corresponds to an areain which many persons gather in an event such as a festival or aconcert. This can be implemented by performing V2X communication betweenportable terminals possessed by the persons and the communication device3, and utilizing obtained V2X information, as described above. This canprevent a vehicle, for example, from travelling in an area in which manypersons have gathered due to an event such as a festival or a concert.

An example of a function configuration of the communication device 3according to the embodiment is described next with reference to FIG. 7.As illustrated in FIG. 7, the communication device 3 is configured by acommunication unit 71, a controller 72, and a storage 78, and thecontroller 72 is further configured by a processing unit 73, adetermination unit 74, a display controller 75, a detector 76, and aspecification unit 77. The configuration of the communication device 3is not limited to the configuration above, and the communication device3 may include other components.

The communication unit 71 performs radio communication with an externaldevice, and receives communication information (V2X information)according to a preset communication condition. Specifically, thecommunication unit 71 includes the function of the communication driver20 illustrated in FIG. 2, and receives vehicle information and roadsidemachine information that are output from another communication device 3and the roadside machine 4. In a case in which V2X information iscommunicated, the communication unit 71 is configured such that radiocommunication of 760 MHz and radio communication of 5.9 GHz can beperformed in Japan and in North America and Europe, respectively. Thereceived vehicle information and roadside machine information are storedin the storage 78, In addition, the communication unit 71 regularly orirregularly outputs vehicle information of the vehicle 2 mounted withthe communication device 3 to the outside. The roadside machine 4 as anexternal device that performs radio communication with the communicationunit 71 includes a communication unit that has a configuration basicallysimilar to that of the communication device 3 such that radiocommunication can be performed with the communication device 3.

The control unit 72 controls the operation of the communication device3. Specific control is performed by the processing unit 73, thedetermination unit 74, the display controller 75, the detector 76 andthe specification unit 77.

The processing unit 73 includes the roadside machine system servicemanagement function 25 and the inter-vehicle system service managementfunction 26, and the processing unit 73 updates respective prescribedservices on the basis of the vehicle information, the roadside machineinformation, and the local-vehicle information that have been obtained.

The determination unit 74 determines whether a prescribed service shouldbe provided in accordance with the received communication information.Specifically, the determination unit 74 includes a V2X managementfunction 27 and a map display function 28, and determines whether aprescribed service should be provided in accordance with an updateresult of the processing unit 73.

When a prescribed service should be provided according to adetermination result, the display controller 75 displays displayinformation needed to provide the prescribed service on a map displayedon a display unit such as the navigation display 30. In addition, thedisplay controller 75 may display the display information on the mapaccording to the movement of a moving body (such as an oncomingvehicle). Stated another way, the display controller 75 displays an icondisplayed on the map that indicates, for example, an oncoming vehiclewhile moving the icon over time.

The detector 76 detects whether the specified vehicle described laterexists in accordance with the received V2X information (such as theroadside machine information or the vehicle information).

The specification unit 77 specifies a travelling route of the specifiedvehicle. The specification unit 77 obtains the travelling route of thespecified vehicle that has been predicted from the speed information ofthe specified vehicle, the steering angle of a steering wheel, and theinformation indicated by the direction indicator, for example, via thecommunication unit 71. The specification unit 77 is configured to heable to specify the travelling route of the specified vehicle such thatthe obtained travelling route and the position information of thespecified vehicle match the latitude and longitude on the map.

The storage 78 stores a program for causing the controller 72 to performvarious processes, and also stores, for example, V2X information, suchas the vehicle information or the roadside machine information, and thelocal-vehicle information.

An example of a hardware configuration for implementing thecommunication device 3 according to the embodiment is described nextwith reference to FIG. 8. As illustrated in FIG. 8, the hardwareconfiguration includes, for example, a central processing unit (CPU) 81,a hard disk drive (HDD) 82, a random access memory (RAM) 83, a read-onlymemory (ROM) 84, an input interface (I/F) 85, a radio 86, and a bus 87.The CPU 81, the HDD 82, the RAM 83, the ROM 84, the input interface(I/F) 85, and the radio 86 are connected to each other for example, viathe bus 87.

The CPU 81 reads a program (such as a communication program) forperforming various processes of the communication device 3, the programhaving been stored in the HDD 82 or the like, temporarily stores theread program in the RAM 83, and performs the various processes accordingto the program. The CPU 81 principally functions as the controller 72described above.

In the HDD 82, an application program for performing the variousprocesses of the communication device 3, data needed for the processesof the communication device 3, and the like are stored. The HDD 82principally functions as the storage 78 described above.

The RAM 83 is a volatile memory, and a portion of an operating system(OS) program or an application program to be executed by the CPU istemporarily stored in the RAM 83 Various types of data needed to performprocessing by using the CPU 81 are also stored in the RAM 83.

The ROM 84 is a non-volatile memory, and stores a program such as a bootprogram or a basic input/output system (BIOS).

The input interface (I/F) 85 receives information that is input via aremote controller, a touch panel, or the like that is not illustrated.

The radio 86 transmits or receives data (such as V2X information)to/from the outside (such as the communication device 3 or the roadsidemachine 4), and principally functions as the communication unit 71described above.

The bus 87 is a route that mediates transmission and reception of acontrol signal, a data signal, and the like among respective devices.

An example of a sequence of processing for Providing a prescribedservice of the communication device according to the embodiment isdescribed next with reference to FIG. 9. As illustrated in FIG. 9,local-vehicle position information that is regularly or irregularlyupdated is stored in the local-vehicle information DB 23 (s1). When thetime to update a prescribed service (an update time) comes (s2), the V2Xmanagement function 27 issues a service update report of the prescribedservice (s3 and S8). In response to the service update report,local-vehicle information is obtained from the local-vehicle informationDB 23 (s4), and another-vehicle information is obtained from theinter-vehicle secondary DB 22 b (s5) The inter-vehicle system servicemanagement function 26 updates respective prescribed services accordingto the obtained local-vehicle information and another-vehicleinformation (s6). Update results of the respective prescribed servicesare stored in the inter-vehicle tertiary DB 22 c (s7) As an example, anupdate result in a case in which a prescribed service is the right-turncollision prevention support service includes, for example, the positioninformation of an oncoming vehicle with respect to the position of thelocal vehicle.

In response to the service update report (s8), local-vehicle informationis obtained from the local-vehicle information DB 23 (s9), and road, idemachine information is obtained from the road-vehicle secondary DB 21 b(s10). The roadside machine system service management function 25updates the respective prescribed services according to the obtainedlocal-vehicle information and roadside machine information (s11). Updateresults of the respective prescribed services are stored in theroad-vehicle tertiary DB 21 c (s12). As an example, an update result ina case in which a prescribed service is the right-turn collisionprevention support service includes, for example, the positioninformation of a pedestrian or the like in an intersection with respectto the position of the local vehicle.

Data of the update result is obtained from the road-vehicle tertiary DB21 c (s13), and data of the update result is obtained from theinter-vehicle tertiary DB 22 c (s14). The V2X management function 27determines whether the prescribed service should be provided inaccordance with the update results, and when the prescribed serviceshould be provided, the V2X management function 27 obtains information(display information) needed to provide the prescribed service (s15).Only the obtained display information is stored in (written to) the V2Xdisplay information DB 24 (s16). The stored display information (data)is read (s17), and the map display function 28 displays, for example, anicon that indicates a pedestrian or the like on a map (s18).

An example of a flow of processing for providing a prescribed service ofthe communication device 3 according to the embodiment is described nextwith reference to FIG. 10. When the time to update a prescribed servicecomes, the communication device 3 obtains local-vehicle information fromthe local-vehicle information DB 23, obtains another-vehicle informationfrom the inter-vehicle secondary DB 22 b, and obtains roadside machineinformation from the road-vehicle secondary DB 21 b (step S1001). Thecommunication device 3 updates the prescribed service according to thelocal vehicle information and the another-vehicle information that havebeen obtained (step S1002), and also updates the prescribed serviceaccording to the local-vehicle information and the roadside machineinformation that have been obtained (step S1003).

The communication device 3 obtains display information to be displayedon a map according to update results of respective updates, and displaysan icon or character information indicating a pedestrian, a vehicle, orthe like on the map (step S1004).

In the description above, when a vehicle or a pedestrian exists aroundthe local vehicle at an intersection or the like, an icon indicating thevehicle or the pedestrian is displayed in a corresponding position on amap such that safe driving can be supported. Here, a communicationdevice is described that displays, on a map, the movement of a specifiedvehicle that is, for example, an emergency vehicle in an emergency, suchas an ambulance, a fire engine, a police car, or a vehicle of a gascompany for coping with a gas leak and the like, when the specifiedvehicle exists around the local vehicle. In the case of a supportservice fore reporting the approach of a special vehicle to a driveraccording to V2X information, communication device mounted on thevehicle 2 can obtain, for example, a difference in the type of anemergency vehicle, such as the ambulance, the fire engine, the policecar, or the vehicle of the gas company for coping with a gas leak andthe like, in inter-vehicle communication. The communication devicemounted on the vehicle 2 can also obtain, for example, identificationinformation (ID) of the emergency vehicle in inter-vehiclecommunication.

First, a display on a map of a specified vehicle, for example, in a casein which the specified vehicle is travelling towards the local vehicleon an opposite lane is described with reference to FIGS. 11A and 11B. Asillustrated in FIG. 11A, assume that a specified vehicle 110 isapproaching the local vehicle 111. A communication device 3 of the localvehicle 111 performs inter-vehicle V2X communication with acommunication device of the specified vehicle 110, and obtains vehicleinformation (V2X information) of the specified vehicle 110. The vehicleinformation of the specified vehicle 110 may be obtained by beingreported from the emergency information, reporting system describedabove in V2X communication.

The communication device 3 detects whether a prescribed specifiedvehicle exists in accordance with the obtained V2X information. When theexistence of the prescribed specified vehicle is detected, displayinformation (characters or an icon) relating to the prescribed specifiedvehicle is displayed on the map.

Specifically, the obtained vehicle information includes information thatspecifies the specified vehicle 110 (such as identificationinformation), and the communication device 3 determines whether anapproaching vehicle is the specified vehicle 110 in accordance with theincluded information and information for specifying a specified vehiclethat has been stored in the storage 78 or the like. When it isdetermined that the approaching vehicle is the specified vehicle 110, anicon or the like that indicates the specified vehicle 110 is displayedaccording to the position information of the local vehicle 111 and theobtained vehicle information of the specified vehicle 110 in such a waythat the icon or the like is superimposed onto a map displayed on thenavigation display 30 described above. An example of the display isillustrated in FIGS. 11A and 11B.

FIG. 11A illustrates an example of a display in a case in which apositional relationship on a map between the specified vehicle 110 andthe local vehicle 111 is viewed from the top. The communication device 3displays an icon indicating a moving body (the specified vehicle 110) ona map in accordance with the movement of the moving body. By doing this,the icon indicating the specified vehicle 110 moves over time, and isdisplayed so as to be approaching an icon indicating the local vehicle111. The same is applied to FIG. 11B. The communication device 3associates the position information including longitude and latitude ofthe local vehicle 111 with map information in order to display the localvehicle 111 on the map, and the communication device 3 displays the iconindicating the local vehicle 111 on the navigation display 30 such thatthe icon indicating the local vehicle 111 is superimposed onto the map.The local vehicle 111 is arranged in such a way that the positioninformation of the local vehicle 111 matches nodes or links in the mapinformation by performing map matching processing. The communicationdevice 3 associates the position information including longitude andlatitude of the specified vehicle 110 with the map information in orderto display the specified vehicle 110 on the map, and displays an iconindicating the specified vehicle 110 on the navigation display 30 insuch a way that the icon indicating the specified vehicle 110 issuperimposed onto the map The specified vehicle 110 is arranged in sucha way that the position information of the specified vehicle 110 matchesthe nodes or links in the map information by performing the map matchingprocessing. The map matching processing is performed at each fixeddistance of the local vehicle 111 and at each prescribed distance of thespecified vehicle 110. In the map matching processing, a process forarranging the present positions of the local vehicle 111 and thespecified vehicle 110 on the road on the map is performed. In the mapmatching processing, when the present locations of the local vehicle 111and the specified vehicle 110 are not on the road, positions on the roadnear the present positions of the local vehicle 111 and the specifiedvehicle 110 are estimated as the present positions of the local vehicle111 and the specified vehicle 110. In the map matching processing, whenthe present locations of the local vehicle 111 and the specified vehicle110 are on the road, the positions on the road of the local, vehicle 111and the specified vehicle 120 are estimated as present positions. Theicon indicating local vehicle 111 and the icon indicating the specifiedvehicle 110 are distinguished from each other by using identificationinformation (ID), and are displayed.

FIG. 11B illustrates an example of a display in a case in which the,specified vehicle 110 approaching the local vehicle 111 illustrated inFIG. 11A is viewed from a side of the local vehicle 111. The iconindicating the specified vehicle 110 approaches the icon indicating thelocal vehicle 111 over time Stated another way, the icon indicating thespecified vehicle 110 is enlarged over time. FIG. 11B also displays apedestrian 112 in an intersection. By doing this, the local vehicle 111can be stopped on a road shoulder or the like with time to spare inorder not to obstruct the travelling of the specified vehicle 110. Whenthe local vehicle 111 and the specified vehicle 110 pass each other, andwhen a distance between both of the vehicles is greater than or equal toa prescribed distance or an elapsed time period after passing each otheris greater than a prescribed time period, the icon indicating thespecified vehicle 110 disappears from the map. An enlarged icon may bedisplayed when the specified vehicle 110 turns at an intersection. Thesize of the icon may be changed according to a change in a scale of theheight of a building. The icon may be di splayed so as to be caused toblink. The size of the icon does not always need to be changed.

The specified vehicle 110 may be displayed on the map of the navigationdisplay 30 as described above or the existence of the specified vehicle110 may be displayed on the display section of a tachometer rather thanon the map.

In addition, which traffic lane of a plurality of traffic lanes thespecified vehicle 110 is travelling in may be displayed on the map orthe like, by using a not-illustrated high-accuracy locator.

A display of a specified vehicle on a map, for example, in a case inwhich the specified vehicle exists around the local vehicle is describednext with reference to FIG. 12. FIG. 12 a diagram in a case in which anurban district lined with a plurality of buildings 123 including ahospital 122 is viewed from the top. As illustrated in FIG. 12, assumethat a specified vehicle 120 is travelling towards the hospital 122 inorder to transport a person with an emergency situation or the like. Inthis case, a communication device 3 of the local vehicle 121 performsV2X communication with a communication device of the specified vehicle120, and the like, and receives (obtains) V2X information. Thecommunication device 3 of the local vehicle 121 detects whether aspecified vehicle exists in accordance with the received V2X information(roadside machine information or vehicle information). Specifically, thecommunication device 3 of the local vehicle 121 determines whether thespecified vehicle 120 exists in accordance with the obtained V2Xinformation and information for specifying a specified vehicle that hasbeen stored in the storage 78 or the like. As a result of thedetermination, in the case of the example above, it is recognized thatthe specified vehicle 120 exists.

However, when the specified vehicle 120 exists in the vicinity, but whenthe positional relationship between the local vehicle 121 and thespecified vehicle 120 is as illustrated in FIG. 12, the specifiedvehicle 120 does not always turn to the right and pass the local vehicle121. This is because the specified vehicle 120 may travel straightahead. In a case in which the specified vehicle 120 travels straightahead, the local vehicle 121 and the specified vehicle 120 do not passeach other, and therefore the specified vehicle 120 can travel withoutstopping the local vehicle 121 on a road shoulder.

The travelling of the specified vehicle 120 basically has a travellingrule, and it is assumed, for example, that the travelling rule includesa rule wherein the specified vehicle 120 travels with priority given toa road with a large width (a main street) Under the rule above, when thewidth of a road 124 that one block ahead when viewed from the specifiedvehicle 120 (a road on a right-hand side of a road 123 on which thelocal vehicle 121 is travelling) is greater that the width of the road123 on which the local vehicle 121 is travelling, the specified vehicle120 does n turn to the right but travels straight ahead, and turns tothe right so as to travel on the road 124.

Accordingly, the communication device 3 of the local vehicle 121specifies a travelling route of the specified vehicle. Specifically, thecommunication device 3 of the local vehicle 121 recognizes the existenceof the specified vehicle 120, and compares the width of the road 123 onwhich the local vehicle 121 is travelling with the width of a road onwhich the specified vehicle 120 is predicted to travel. As a result ofthis, when it is determined that the width of the road 123 on which thelocal vehicle 121 is travelling is greater, the road 123 is specified tobe a travelling route of the specified vehicle 120. By doing this, it isdetermined that the specified vehicle 120 will turn to the right andwill pass the local vehicle 121 (travelling routes will overlap eachother).

In this case, the communication device 3 displays a line or the likethat indicates the travelling route of the specified vehicle 120, on aroad on the map that corresponds to a road on which the local vehicle121 will travel. Consequently, a specified vehicle that affects thetravelling of the local vehicle can be grasped even in a place where thevisibility is actually poor, and a sudden accident can be coped with.

When it is determined that both of the vehicles will not pass eachother, the line indicating the travelling route of the specified vehicle120 does not need to be displayed on the map. In this case, the lineindicating the travelling route of the specified vehicle 120 is notdisplayed. This is because the specified vehicle 120 does not obstructthe travelling of the local vehicle 121. Even when it is determined thatboth of the vehicles will not pass each other, the line indicating thetravelling route of the specified vehicle 120 may be displayed. In thiscase, the mariner in which the line is displayed may be changed, forexample, by drawing the line with a broken line.

The roadside machine information transmitted from the roadside machine 4via radio communication is normally transmitted within a range of 200 mto 300 m. In general, the accuracy of road information transmitted froma roadside machine is higher than the accuracy of road informationspecified by a car navigation device or a portable terminal such as asmartphone having a navigation function. Accordingly, when thelocal-vehicle position is within a range in which the roadside machineinformation can be received from the roadside machine 4, thecommunication device 3 can display the local vehicle position specifiedby the navigation function and the longitude and latitude specified byinformation from the specified vehicle and the road information from theroadside, machine on the map in such a way that the local-vehicleposition and the longitude and latitude overlap each other. When thelocal-vehicle position is not within the range in which the roadsidemachine information can be received from the roadside machine 4, thecommunication device 3 displays the local-vehicle position specified bythe navigation function and the longitude and latitude specified by theinformation from the specified vehicle and the road informationindicated by the navigation function on the map in such a way that thelocal-vehicle position and the longitude and latitude overlap eachother. In other words, the communication device 3 may be configured soas to be able to switch the road information between the roadsidemachine information from the roadside machine 4 and the informationindicated by the navigation function of the communication device 3. Thecommunication device 3 may be configured, for example, such that thecommunication unit can determine that the local-vehicle position iswithin a range in which the roadside machine information fails to bereceived from the roadside machine 4 when the intensity of radiocommunication from the roadside machine 4 is smaller than a prescribedvalue or a prescribed position.

Even if the attention-attracting display is used, the driver may notgrasp accurately where the vehicle or pedestrian exists, and the drivermay become even more anxious. Therefore, the attention-distractingdisplay has not been useful to support safe driving. The embodiment ofthe present invention can provide a communication device whichaccurately informs the driver of the position where the vehicle orpedestrian exists with regard to the local vehicle, better supportingsafer driving.

The above explanation was made on the basis of a left-hand trafficsystem which vehicles travel on the left side of a road. The aboveexplanation should therefore be modified where needed in a relevantmanner (i.e., reversed) to match a right-hand traffic system in whichvehicles travel on the right side of a road.

The present invention is not limited to the embodiment above with nochange, and components can be varied and embodied without departing fromthe gist of the embodiment above in an implementing stage. Variousinventions can be made by appropriately combining a plurality ofcomponents disclosed in the embodiment above. As an example, all of thecomponents disclosed in the embodiment may be appropriately combined. Itgoes without saying that various variations or applications can be madewithout departing from the spirit of the invention.

What is claimed is:
 1. A communication device mounted on a moving body,the communication device comprising: a memory that receivescommunication information according to a present communicationcondition; a processor that determines whether a service is provided inaccordance with the received communication information, the processorexecuting a Process according to the program; a display controller thatdisplays display information needed to provide, the service on a mapdisplayed on a display unit, when the service is provided according to aresult determined by the processor; and a detector that detects whetheran emergency vehicle exists in accordance with the receivedcommunication information, wherein the display controller displays anicon indicating the emergency vehicle on the map in the case ofexistence of the emergency vehicle is detected, and wherein the displaycontroller makes the icon indicating the emergency vehicle on the mapdisappear in the case of the emergency vehicle and the moving body passeach other, and a distance between both is greater than or equal to aprescribed distance or an elapsed time period after passing each otheris greater than a prescribed time period.
 2. The communication deviceaccording to claim 1, wherein when the display information includesinformation relating to the moving body, the display controller displaysthe display information on the map according to a movement of the movingbody.
 3. The communication device according to claim 1, wherein theprocessor specifies a travelling route of the emergency vehicle on thebasis of a traveling rule, and wherein the display controller performs:displaying the specified travelling route on the map when the specifiedtravelling route overlaps the travelling route of a vehicle mounted withthe communication device; and not displaying the specified travellingroute when the specified travelling route does not overlap thetravelling route of the vehicle mounted with the communication device.4. The communication device according to claim 1, wherein the presentcommunication condition that V2X information relating to V2X iscommunicated.
 5. The communication device according to claim 1, whereinthe communication information includes at least one of roadside machineinformation obtained from a roadside machine, moving body informationobtained by the moving body, and emergency information obtained from anemergency information reporting system.
 6. The communication deviceaccording to claim 1, wherein the communication information includeslocal-vehicle information on a basis of operating information of themoving body, another-vehicle information on a basis of operatinginformation of an another vehicle from another communication devicemounted in the another vehicle, and roadside machine, information on abasis of a detection result in a surrounding environment of the movingbody from a roadside machine installed in the surrounding environment ofthe moving body.